I don't have a direct answer for you, but make sure you are sharpening at print size. In Photoshop you need to set the screen DPI correctly to get the 1:1 preview. I don't know how the retina display impacts this but it should be pretty obvious if you aren't seeing the 1:1 ratio.

I've been very happy with the Canon Pixma 9000 Mk II. (I also use the 9500 Mk II depending on what type of ink you prefer.)

I wasn't looking for a home printer at the time but Canon ran huge rebate if you bought a printer and camera. Lots of people took advantage of it and dumped the printers on eBay. I got mine new and unopened for $180. Might want to keep an eye out for any future Canon offers then check eBay.